bio AS

• what are DNA and RNA vital to?

  all biological processes and the formation of most of the other importamt biological molecules.
• what are nucleotides?


  the monomers that join to form nucleic acids and they are made of 3 parts.
• what are the 3 parts that make up nucleotides?


  - a pentose sugar.

  - a phosphate group.

  - a base containing nitrogen.
• what is a phosphate group?

  a combination of phosphorus and oxygen atoms.
• what does the base containing nitrogen go in a nucleotide?

  identifies the different nucleotides.
• how are nucleotides bonded together?

  through condensation reactions.
• what is the name for 2 nucleotides?

  a dinucleotide.
• what is more than 2 nucleotides bonded together called?

  a polynucleotide.
• what is the bond called that forms between nucleotides through a condensation reaction?

  phosphodiester bond.
• what does the bond formed in a condensation reaction between nucleotides occur between which part of the nucleotide?

  the phosphate group of 1 atom and the pentose sugar of another atom.
• what is the backbone made of in DNA?

  a sugar/phosphate backbone.
• what are the 4 bases in DNA?

  Adenine, Thymine, Guanine, Cytosine
• what base is specific to RNA?


  uracil.
• What does RNA stand for?

  ribonucleic acid
• what is RNA?


  a nucleic acid formed from a chain of nucleotides. They are short, uncomplicated nucleotides and usually a single chain.
• what is the pentose sugar always in RNA?

  ribose.
• what are the possible bases in RNA?

  Adenine, Guanine, Uracil, Cytosine
• what base is not present in RNA?


  Thymine.
• where does the name ribonucleic acid come from?


  the fact that the pentose sugar in its nucleotides is always ribose.
• what is one of RNA's main functions?


  to transfer genetic info from the DNA to make ribosomes, the ribosomes then read the RNA to make a polypeptides in a process called translation.
• what structure does DNA have?

  a double helix structure.
• what does DNA stand for?

  deoxyribonucleic acid.
• what is DNA a vital part of?

  the storage of genetic information.
• when was the double helix discovered?

  1953.
• why is DNA more complicated than RNA?

  DNA is formed from 2 polynucleic chains that are longer than RNA chains. In DNA the bases pair up and create links between the 2 strands.
• what are the bases found in DNA?


  adenine, guanine, cytosine, thymine
• what does the structure of the bases allow in DNA?

  allow them to create links, which is what the base pairing is specific.
• what does adenine pair with in DNA?


  thymine.
• what does guanine pair with in DNA?

  cytosine.
• what are adenine and guanine known as?

  the purine bases with a double ring structure.
• what are cytosine and thymine (and uracil in RNA) known as?

  the pyrimidine bases with a single ring structure.
• how many bonds do thymine and adenine form?

  2 hydrogen bonds.
• how many bonds do guanine and cytosine form?

  3 hydrogen bonds.
• why is DNA names DNA?

  because the pentose sugar is always deoxyribose.
• what creates the twists of the 2 strands into a double helix in DNA?


  the base painting and the interactions and bonds.
• what do the paired bases form in DNA?

  the rungs of a twisted spiral ladder.
• what good does DNA being a stable molecule cause?

  its suited to its role in storing genetic material.
• where does part of DNA's stability come from? how?


  the phosphate-sugar backbone, the twisting of the backbone provides a chemical shield that protects the more chemically reactive nitrogenous bases.
• where does DNA's increased rigidity and stability come from?

  the combination of bases.
• which bases are good for the DNA to have more of for further stability? why?

  guanine and cytosine bc there are 3 bonds and so more hydrogen bonds so further stability.